Thinking about a new solar setup for my 5th wheel

Seems if I need to, I could use the existing 10 gauge wires to pull a larger wire through the ceiling cavities if I need to but don't really know where it runs. The reply before last indicates I might want 500 plus watts. I have a lot of clear roof space on my Alpenlite. If I do it I'd like to have sufficient power to run the frig and normal florescent bulbs ( we don't watch TV either) for a week or so not hooked up. We like national forests. Is this possible or am I caught up in an impractical idea?